A Liquid Crystal Display (LCD) is a display device with a thin plane, formed by a certain number of color pixels or black and white pixels and disposed in front of a light source or a reflective panel. The liquid crystal display is favored by everyone and becomes a mainstream display due to its low power consumption, high-definition, small size and light-weight etc. The liquid crystal display is widely used in various electronic products like a computer device having a display screen, a mobile phone or a digital photo frame and so on, and wide visual angle technology is one of the developing focuses of the liquid crystal display at present. However, if a side visual angle or a squint angle is too large, color shift phenomenon may occur in the wide-visual-angle liquid crystal display.
As for the problem of color shift in the wide-visual-angle liquid crystal display, a 2D1G technology is employed in the field at present for improvement. The so-called 2D1G technology is a technology, wherein dividing every pixel unit in the liquid crystal panel into a main pixel region and a sub pixel region of which areas are different from each other, and the main pixel region and the sub pixel region in the same pixel unit connect to different data lines and the same gate line. By inputting different data signals (different gray scale values) into the main pixel region and the sub pixel region, different display brightness and squint brightness are generated, thereby decreasing the color shift generated by viewing from the side or at a squint angle. One pixel unit has one gray scale value, by setting gray scale values of each of the main pixel region and the sub pixel region, the combination of the gray scale values of the main pixel region and the sub pixel region can achieve the purpose of decreasing the color shift.
In the actual hardware device, the liquid crystal display panel is driven by a gate driving module and a source driving module respectively providing a scanning signal and a data signal to the liquid crystal display unit, a voltage difference between different data signal voltages and the common electrode voltage causes different rotation angles of the liquid crystal, thus a difference in brightness will be generated, that is to say, the display of the liquid crystal panel forms different gray scales. In the liquid crystal panel, a relationship curve between a data signal voltage and a gray scale is called Gamma curve, take a 8-bit liquid crystal panel for example, it can display 28=256 gray scales, which are corresponding to 256 different Gamma voltages, and the Gamma voltage is 2 to the N-th power parts divided from the changing process from white to black. Therefore, in the 2D1G technology, it is needed to generate two groups of Gamma voltages of 0-255 gray scales.